diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -306,11 +306,14 @@
     return Match(Cst);
 
   // FIXME: Add support for vector UNDEF cases?
+  // FIXME: Support SPLAT_VECTOR on fixed vectors. Should it call Match once
+  // or NumElements times?
+  EVT VT = Op.getValueType();
   if (ISD::BUILD_VECTOR != Op.getOpcode() &&
-      ISD::SPLAT_VECTOR != Op.getOpcode())
+      !(ISD::SPLAT_VECTOR == Op.getOpcode() && VT.isScalableVector()))
     return false;
 
-  EVT SVT = Op.getValueType().getScalarType();
+  EVT SVT = VT.getScalarType();
   for (unsigned i = 0, e = Op.getNumOperands(); i != e; ++i) {
     if (AllowUndefs && Op.getOperand(i).isUndef()) {
       if (!Match(nullptr))
diff --git a/llvm/test/CodeGen/AArch64/sve-fixed-length-int-div.ll b/llvm/test/CodeGen/AArch64/sve-fixed-length-int-div.ll
--- a/llvm/test/CodeGen/AArch64/sve-fixed-length-int-div.ll
+++ b/llvm/test/CodeGen/AArch64/sve-fixed-length-int-div.ll
@@ -968,4 +968,20 @@
   ret void
 }
 
+; This used to crash because isUnaryPredicate and BuildUDIV don't know how
+; a SPLAT_VECTOR of fixed vector type should be handled.
+define void @udiv_constantsplat_v8i32(<8 x i32>* %a) #0 {
+; CHECK-LABEL: udiv_constantsplat_v8i32:
+; CHECK: ptrue [[PG:p[0-9]+]].s, vl[[#min(div(VBYTES,4),8)]]
+; CHECK-NEXT: ld1w { [[OP1:z[0-9]+]].s }, [[PG]]/z, [x0]
+; CHECK-NEXT: mov [[OP2:z[0-9]+]].s, #95
+; CHECK-NEXT: udiv [[RES:z[0-9]+]].s, [[PG]]/m, [[OP1]].s, [[OP2]].s
+; CHECK-NEXT: st1w { [[RES]].s }, [[PG]], [x0]
+; CHECK-NEXT: ret
+  %op1 = load <8 x i32>, <8 x i32>* %a
+  %res = udiv <8 x i32> %op1, <i32 95, i32 95, i32 95, i32 95, i32 95, i32 95, i32 95, i32 95>
+  store <8 x i32> %res, <8 x i32>* %a
+  ret void
+}
+
 attributes #0 = { "target-features"="+sve" }